There has been known a method of heating a glass sheet to a temperature close to a softening point in a heating apparatus, forming the glass sheet by a forming mold or by own weight of the glass sheet, and quenching the glass sheet in an air-cooling/tempering apparatus to produce an automotive window glass sheet. Such an air-cooling/tempering apparatus is constituted by a plurality of upper nozzle chambers provided on an upper blowing member and a plurality of lower nozzle chambers provided on a lower blowing member, and the apparatus is configured to blow an air against an upper surface of a bent glass sheet from air-blowing openings of the plurality of upper nozzle chambers, and to blow an air against a lower surface of the glass sheet from air-blowing openings of the plurality of lower nozzle chambers, to air-cool/temper the glass sheet.
An air-cooling/tempering apparatus disclosed in JP-A-2006-521274 (hereinafter referred to as Patent Document 1) has, as shown in FIG. 7, an upper blowing member (blowing head) 1 and a lower blowing member (blowing head) 2 disposed above and below a glass sheet to quench the glass sheet, and these blowing members 1, 2 are each constituted by a plurality of blade-shaped members (plenums) 3, 3 . . . arranged with a gap from one another into a comb-tooth shape, and on a front face of each of these blade-shaped members 3, 3 . . . , a plurality of air-blowing openings 4, 4 . . . are formed so as to be dotted. These air-blowing openings 4, 4 . . . are formed so as to be inclined from one another on the front end face of each blade-shaped member 3 to obtain a divergent flow of air. However, since the blade-shaped member 3 linearly extends in a direction perpendicular to a conveying direction of a glass sheet G indicated by an arrow A in FIG. 8, the plurality of air-blowing openings 4, 4 . . . dotted on the front end face of each blade-shaped member 3 are linearly arranged in plan view. Further, the arrangement of the air-blowing openings 4, 4 . . . extends along a line of the blade-shaped member 3 curved in its extending direction, and the curvature of the arrangement is determined so as to conform to an average local curvature of the bent glass sheet G. Namely, in the air-cooling/tempering apparatus of Patent Document 1, the blade-shaped members 3, 3 . . . are constructed so that the distance from the plurality of air-blowing openings 4, 4 . . . to the bent glass sheet G is substantially uniform.